The developers don't either. They can (and do) provide a wide range of content. They only need to decide which parts they'll put in, which they'll leave out and in which order. They certainly don't need to choose between, say, end-game content and SGRAs. They may choose to (which is their right as the makers of the game) but they don't need to.
EDIT: If you're actually wondering what I think the majority of players want, I think the player population is too split to agree on any one particular type of content and as cynical as it may be of me I definitely think most groups would claim the majority want what they do. I certainly don't think SGRAs are a priority for the majority of players but I doubt crafting is either. I can't really speak for the majority because I don't frequent most of the other boards.
That's what I mean by vetoing things on the basis of disliking them and for no other reason.
Will have to disagree. I think the devs do need to figure out what the majority of players want, and out of that, what is the most cost effective for them, while, if we're lucky, implementing the things that are nice for some, but likely not cost effective.